An Operations Manager for a Well Servicing Company in Texas, Died When a Length of Pipe
Mounted on Top of a Skid-mounted Mud Pump Broke Loose and Struck Him in the Head

SUMMARY

On October 29, 1998, a 63 year-old male operations manager (the victim)
died when a length of pipe mounted on top of a skid-mounted mud pump broke
loose and struck him in the head. The work crew was in the process of sealing a
well. They had finished pumping in cement and were starting to pump in water to
displace the cement down to 10,000 feet. As the operations manager leaned over
and looked into one of the two mud mixing tanks, he was struck on the side of
the head by a length of pipe (return line) from the pump that had not been
secured.

The TX FACE investigator concluded that to reduce the likelihood of
similar occurrences, employers should:

ensure all piping (discharge and return lines) that are mounted on top of mud pump tanks
are secured.

develop a checklist for mud pump operators and supervisors to ensure that all the steps
necessary to conduct a cementing operation have been performed.

INTRODUCTION

On October 28, 1998, a 63 year-old male operations manager
(the victim) died when a length of pipe mounted on top of a skid-mounted mud pump
broke loose and struck him in the head. The TX FACE program officer was
made aware of the incident by the regional OSHA office on December 17, 1998. A
visit to another site by the TX FACE program officer, where the mud pump had
been relocated, was made on February 17, 1999. The new operations manager and
the mud pump operator were interviewed. Pictures were taken of the mud pump.
An autopsy report was obtained.

The employer was a well servicing company. The company
employed 50 workers, two of whom performed the same
duties as the victim. The employer had been in business for 32 years. There
were six other workers at the site at the time, however, no one witnessed the
event. The mud pump operator was standing next to the victim but had his back
to him.

The employer's safety program was managed by the operations
manager. A written safety program was in place but there were no written work
procedures specific to the victim's task. Safety meetings were conducted on a
monthly basis. Tool pushers would also conduct daily job site talks on what was
to be done that day along with any safety related issues. The company hired
experienced workers so new hire and/or refresher training was not conducted.

The victim had been employed with the company for eight years. He had
26 years experience in well servicing which included cementing wells.

The company conducted pre-employment physicals and drug screening. This
was the first fatality experienced by the employer.

INVESTIGATION

A work crew for the employer was in the process of sealing a well. They
were performing an operation referred to as "squeezing off perforations" or
"squeezing". It involved pumping cement into the hole and then pumping in water to
displace the cement further down into the well formation. They were displacing
the cement down to a depth of 10,000 feet.

A tri-plex, skid-mounted mud pump was used for this operation. The mud
pump was equipped with two mixing tanks. Piping ran across the top of the two
tanks which included two discharge lines and two return lines. Pipes were
normally secured with u-clamps. In this incident, one return line had not been
properly secured.

The work crew first pumped water into the annulus, which is the area
surrounding the casing in a well. Cement, with a retarder mixed in to prevent
the cement from hardening too soon, was then pumped into the well. The mud
pump operator pumped in a total of 15 barrels of cement. After pumping in the
cement, the mud pump operator started to pump in water in order to displace
the cement down to a depth of 10,000 feet.

The victim was assisting the mud pump operator by looking into the
mixing tanks. He was observing the "notches" on the inside of the tank which indicate how
much water had been pumped into the well. The mud pump operator was pumping at
1,400 psi. He did not observe any abnormal fluctuations of pressure. The mud
pump piping was rated at 5,000 psi. The relief valve was set at 4,000 psi.

After about 20 barrels of water were pumped,
the mud pump operator heard a loud noise. The victim, who had been leaning over
and looking into one of the mixing tanks, was struck on the upper left side of
the head by the return line which had not been secured. Excessive pressure
caused the return line to flip up and the ball valve to blow off the end of the
return line. The excessive pressure was instantaneous and caused the relief
valve mechanism to fail. The ball valve was never found.

Emergency Medical Services (EMS), Sheriff,
and the Justice of the Peace were notified and they responded to the scene. The
Justice of the Peace pronounced the victim dead at the scene.

CAUSE OF DEATH

(Note: the report hasn't arrived yet.)

RECOMMENDATIONS/DISCUSSION

Recommendation #1 - Employers should ensure all piping
(discharge and return lines) that are mounted on top of mud pump tanks are
secured.

Discussion: The pipes mounted on top of the mud pump
were connected together by "T" and 90 degree "elbow" connections.
Where the pipe is screwed into one of these connections is the point excessive pressure
can cause the "T" or 90 degree "elbow" to rotate. Securing the pipes
to the tank would prevent this from occurring if an excessive amount of pressure builds up.

Employers can refer to the American Petroleum
Institute RP54-1981, Recommended Practices for Occupational Safety and Health
for Oil and Gas Well Drilling and Servicing Operations, para 8.14.3, and
ANSI/ASME Standard B31.1e - 1979 para 122.6 for additional information.

Recommendation #2 - Employers should develop a checklist for
mud pump operators and supervisors to ensure that all the steps necessary to
conduct a cementing operation have been performed.

Discussion: In this
incident, the source of the excessive pressure could not be determined. Workers
can protect themselves from this type of hazard by ensuring equipment is
properly installed up. In this incident the pipe that struck the victim was not
secured. Also the ball valve that was blown off the end of the pipe may have
been closed. It was never found.

Using a
checklist can guide workers through a process that ensures all necessary tasks
are completed and equipment is in the correct configuration.

Please use information listed on the Contact Sheet on the NIOSH FACE
web site to contact In-house
FACE program personnel regarding In-house FACE reports and to gain assistance
when State-FACE program personnel cannot be reached.